require_relative '../../spec_helper'

ruby_version_is ""..."3.1" do
  require_relative 'fixtures/classes'
  require 'matrix'

  describe "Matrix.[]" do

    it "requires arrays as parameters" do
      -> { Matrix[5] }.should raise_error(TypeError)
      -> { Matrix[nil] }.should raise_error(TypeError)
      -> { Matrix[1..2] }.should raise_error(TypeError)
      -> { Matrix[[1, 2], 3] }.should raise_error(TypeError)
    end

    it "creates an empty Matrix with no arguments" do
      m = Matrix[]
      m.column_size.should == 0
      m.row_size.should == 0
    end

    it "raises for non-rectangular matrices" do
      ->{ Matrix[ [0], [0,1] ] }.should \
        raise_error(Matrix::ErrDimensionMismatch)
      ->{ Matrix[ [0,1], [0,1,2], [0,1] ]}.should \
        raise_error(Matrix::ErrDimensionMismatch)
    end

    it "accepts vector arguments" do
      a = Matrix[Vector[1, 2], Vector[3, 4]]
      a.should be_an_instance_of(Matrix)
      a.should == Matrix[ [1, 2], [3, 4] ]
    end

    it "tries to calls :to_ary on arguments" do
      array = mock('ary')
      array.should_receive(:to_ary).and_return([1,2])
      Matrix[array, [3,4] ].should == Matrix[ [1,2], [3,4] ]
    end


    it "returns a Matrix object" do
      Matrix[ [1] ].should be_an_instance_of(Matrix)
    end

    it "can create an nxn Matrix" do
      m = Matrix[ [20,30], [40.5, 9] ]
      m.row_size.should == 2
      m.column_size.should == 2
      m.column(0).should == Vector[20, 40.5]
      m.column(1).should == Vector[30, 9]
      m.row(0).should == Vector[20, 30]
      m.row(1).should == Vector[40.5, 9]
    end

    it "can create a 0xn Matrix" do
      m = Matrix[ [], [], [] ]
      m.row_size.should == 3
      m.column_size.should == 0
    end

    describe "for a subclass of Matrix" do
      it "returns an instance of that subclass" do
        MatrixSub[ [20,30], [40.5, 9] ].should be_an_instance_of(MatrixSub)
      end
    end
  end
end
